NOT venomous but may bite if harassed. Typically found in and around bodies of water. Head is only slightly wider than neck, keeled scales, round pupils. Stocky body with a diamond pattern down the back outlined in black or dark brown. Bold pattern may resemble a chain link fence from above. Typically 30 to 48 inches (76 to 122cm) in length. (J. R. Dixon and J. E. Werler, Texas Snakes: A Field Guide, University of Texas Press, 2000.)